As a processing technology, the laser processing enables cutting, welding, surface treatment, punching, micromachining and other processes of a material with the character of the interaction between the laser ray and the material.
As the application area laser processing expands rapidly, the demand of laser processing device is increasing, and the requirement of the quality of marking is also increasing. The width of the marking is generally required to be about 0.01 mm in the past, but nowadays the width is required to be about micrometers. This requires not only a laser processing device with a high precision, but also an optical system with a high imaging quality.
As an optical system of the laser processing device, the focusing lens plays a substantial role in the quality of the laser processing. However, the traditional focusing lens has a small field of view, with a lower imaging quality, which is difficult to satisfy the requirement of the width of the high-precision marking processed by laser.